You can also pull the queries that differ from the log file if you have "verbose" turned on for your database pools.
In other words, the failure above is because a select returned no rows, while it did return a row in the installation that's working.
If you could dig out that failing query, try it in PSQL, and poke around and tell us more about the table contents we'd have a better chance of figuring out just what's wrong.
